Papillary thyroid cancer stroma - histological and immunohistochemical study

Area of Science:

• Endocrinology
• Oncology
• Pathology

Background:

• Thyroid cancer is the most common endocrine neoplasia, with papillary thyroid cancer (PTC) being the predominant subtype.
• While tumor stroma is crucial for tumor development, histopathological studies have historically focused on tumor cells.
• Increasing incidence of thyroid cancer necessitates a deeper understanding of its microenvironment.

Purpose of the Study:

• To histopathologically and immunohistochemically evaluate the characteristics of tumor stroma in papillary thyroid carcinomas.
• To identify variations in stromal composition and cellularity within different PTC subtypes.

Main Methods:

• Histopathological examination of 18 papillary thyroid carcinoma cases.
• Immunohistochemical analysis using anti-CD34, anti-vimentin, and anti-α-SMA antibodies.
• Evaluation of stromal components including collagen, calcifications, and inflammatory infiltrates.

Main Results:

• Diverse stromal compositions were observed, including fibrous, hyaline, and myxoid types, with collagen-rich axes in some cases.
• Inflammatory infiltrates, primarily lymphocytes, were present in nine cases, with lymphoid nodules in one.
• Immunostaining confirmed well-represented vascularity and an increased presence of fibroblasts and myofibroblasts in the tumor stroma.

Conclusions:

• The tumor stroma in papillary thyroid carcinomas exhibits significant heterogeneity.
• The presence of varied stromal components and cellularity suggests neoplastic cells actively influence and remodel the tumor microenvironment.
• Further research into stromal characteristics could offer new insights into PTC progression and treatment.